HP StorageWorks XP24000 Continuous Access Journal Software User and Reference Guide, v01 (T5278-96001, June 2007)
Continuous Access Journal does not allow the secondary data volume to be online (except while the pair is
split). If the secondary data volume is online, the Continuous Access Journal paircreate operation will fail.
WA RN ING:
If the Continuous Access Journal secondar y data volumes are physically a ttached to the same
host server(s) as the Continuous Access Journal primary d a ta volumes, the following problem can occur:
• When a Continuous Access Journal pair is released, the old secondary data volume is usually
offline. If the host is then restarted, the system administrator may be offered bo th volumes and
asked which volume should be left offline. This can be confusing and prone to error.
If the Continuous Access Journal secondary da ta volumes and p rimary data volumes are co nnected to
the
same host(s), HP strongly recommends that the secondary data volumes are defined to remain
offline to avoid this problem.
Installing the Hardware
Initial installation of the Continuous Access Journal hardware is performed by the user and the HP service
representative. To install the hardware required for Continuous Access Journal operations:
1. User: Ident
ify the locations of the Continuous Access Journal primary and secondary data
volumes (primary data volumes and secondary data volumes), so that the Continuous Access
Journal hardware can be installed and configured properly .
2. HP Service R
epresentative: M ake sure that the primary storage system(s) and secondary storage
system(s)
are configured for Remote Web Console operations (for example, the SVP is conne cted
to a
LAN). S
ee the
HP StorageWorks XP24000 Remote Web Console User’s Guide for
informat
ion and instructions on setting up Remote Web Console operations.
3. HP Service Representative: Make sure that the primary storage systems and secondary storage
systems a re properly configured for Continuous Access Journal operations (for example, cache
and NVS) (see “Cache and Nonvolatile Storage (NVS)”onpage46). Makesure thatthe
desired
system option modes are enabled (see Table 3 on page30). Makesurethat adequate
cache is
installed and available for Continuous Access Journal operations. You must also
consider the amount of Cache Residency Manager d a ta to be stored in ca che when determining
the
required amount of cache.
4. HP Service Representative: M a ke sure that the primary storage systems are configured to report
sense information to the host(s). The seconda ry storage systems should also be a ttached to a
host server to enable reporting of sense information in case of a problem with a seco ndary data
volume or secondary storage system. If the remote site is unattended, the secondary storage
syste
ms should be at tached to a host server at the primary site, so that the system administrator
can
monitor the operational condition of the secondar y storage systems.
5. HP Service Representative: If power sequence control cables are used, set the
power select switch for the cluster to LOCAL to prevent the primary storage system
from being powered off by the host. Also make sure that the secondary storage
system will not be powered off during Continuous Access Jo urnal operations. See
“Managing Power for Storage Systems and Network Relay Devices” on page 1 06 for further
information on powering off/on the primary storage systems and secondary storage systems.
6. HP
Service Representative: Install the Continuous Access Journal remote c opy connections
between the primary storage system(s) and secondary storage system(s). This hardware (optical
fibre cables, switches, and so on) is supplied by the user.
See “Setting up Remote Copy Connections” on page 47 for remote copy configurations.
Distribute the paths between different storage clusters and switches to provide maximum flexibility
a
nd
availability. The logical paths between the primary storage system and secondar y storage
s
ystem must be separate from the logical paths between the host and secondar y storage system.
Setting up Remote Copy Connections
Figure 7 on page48shows theremotecopyconnectionconfigurations for Continuous Access Journal
operations. The primary storage system and secondary storage system for each Continuous Access
Journal pair must be connected via optical fiber cables. If you use multimode shortwave optical fiber
cables, fibre cables up to 1.5 km in length and up to t wo switches are required for distances greater than
XP24000 Continuous Access Journal Software User a nd Reference Guide
47